UL 1203

These requirements cover explosion-proof and dust-ignition-proof electrical equipment for installation and use in hazardous (classified) locations, Class I, Division 1, Groups A, B, C, and D, and Class II, Division 1, Groups E, F, and G, in accordance with the National Electrical Code, NFPA 70.

These requirements also cover explosion-proof electrical equipment for installation and use in Class I, Zone 1, Groups IIA, IIB, and IIC hazardous (classified) locations.

These requirements also cover explosion-proof electrical equipment that has been investigated for use in one or more specific gas or vapor atmospheres with or without additional Class I Groups. See .

These requirements do not cover intrinsically safe electrical circuits of electrical equipment for use in hazardous (classified) locations, or equipment for use in hazardous (classified) locations specifically covered in a separate standard.

These requirements cover equipment for use under the following atmospheric conditions:

1. A minimum ambient temperature of minus 50C (minus 58F);
2. An oxygen concentration not greater than 21 percent by volume; and
3. A nominal barometric pressure of one atmosphere.

A product that contains features, characteristics, components, materials, or systems new or different from those covered by the requirements in this standard, and that involves a risk of fire or of electric shock or injury to persons shall be evaluated using appropriate additional component and end-product requirements to maintain the level of safety as originally anticipated by the intent of this standard. A product whose features, characteristics, components, materials, or systems conflict with specific requirements or provisions of this standard does not comply with this standard